HEPR: Loss of Sea Ice
Marine ecosystems adapted to cold temperatures and seasonal sea ice presumably will shift northward as ocean temperatures warm and sea ice retreats poleward. Addressing these shifts is critical for fisheries management, because nationally important fisheries (>40% U.S. catch) are located primarily within the southern Bering Sea, and for successful co-management of marine mammals, which at least 30 Alaska Native communities depend on.
Some studies of the relationship between the spatial distribution of fish and ice seals and the area covered by Bering Sea ice during spring have begun:
- The National Marine Mammal Laboratory (AFSC) conducted aerial surveys of ice seal distribution during spring and tracking of ice dependent seals using satellite tags in 2006 and 2007; these studies depend on NSF provided helicopter and ship time which may not be available in the future.
- The RACE Division (AFSC) conducted acoustic and Ichthyoplankton surveys during spring near and within ice-covered areas in 2006 and 2007.
Beaufort and Chukchi Seas
Marine Fish Surveys
A Loss of Sea Ice Program goal is to periodically monitor abundance and distribution in northern seas (Chukchi and Beaufort). A Beaufort Sea Marine Fish Survey is planned for 2008. A Chukchi Sea Marine Fish Survey has been proposed for 2008 and depends on available vessel time. Same-year surveys would serve as a baseline to examine climate change effects as well as a comparison between three large marine ecosystems (Bering, Chukchi and Beaufort). Read the press release>
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However NOAA has no programs in place to observe northward shifts in fish and marine mammals. To meet this need, NOAA needs to:
- Expand existing surveys in the southeastern Bering Sea (bottom trawl, acoustic-midwater trawl surveys) to cover the current commercial fishery area and expand gray whale (acoustic and visual surveys), ice seal (aerial survey and satellite tagging) and ocean temperature monitoring.
- Conduct the process-based studies required to understand these changes. Assess impacts of Bering Sea loss of sea ice on vital rates (growth, maturity, and feeding) and movement. Assess whether spatial shifts are creating new biological communities and altering food webs. Forecast distribution and abundance of managed species and the economic and sociological impacts on the commercial and subsistence fisheries of the Bering Sea.
- Monitor fish, shellfish and marine mammal species in the northern Bering Sea where northward expansion of species is expected.
Related Reports and Activities
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